To make the pastry, place the flour and salt on a cold work surface. With a pastry scraper, cut the butter into the flour until half of the butter is the size of peas and the other half is smaller. Make a well in the center of the flour and add half of the water. Push together with your fingertips and set aside any dough that holds together. Add the rest of the water and repeat. Form the mixture into a rough ball. Alternatively, this can be done in a food processor.
On a well-floured surface, roll the dough into a 14-15 inch circle. Trim the edges. Place on a large baking sheet in the refrigerator.
Heat a small skillet over medium heat. Add the bacon and cook until crisp, stirring occasionally. Remove bacon pieces from the pan with a slotted spoon and place on a paper towel to drain. Discard bacon grease.
To make the filling, mix together the goat cheese, ricotta, mozzarella and creme fraiche or sour cream. Mix well and season with salt and pepper.
Preheat the oven to 350F. Remove the pastry from the refrigerator. Spread the cheese over the pastry, leaving a 2-inch border around the edge uncovered. Fold the uncovered edge of the pastry over the cheese, pleating it to make it fit.
Bake until golden brown, 35-40 minutes. Remove from oven and sprinkle Parmesan and cooked bacon on top. Let cool 5 minutes, and then slide the tart off the pan and onto a serving plate. Serve hot, warm, or at room temperature. Garnish with fresh herbs such as parsley or basil if desired.